Technical Field of the Invention
The present invention relates to an apparatus of a bobbin changing type for winding a yarn, such as a synthetic yarn, at a high speed, which apparatus is provided with two bobbin holders, and in which when a package wound on one of the bobbin holders reaches a predetermined amount, winding of the yarn is changed to another bobbin on the other bobbin holder.
As disclosed in Japanese Patent Publication No. Sho 57-25466, a conventionally known yarn winding apparatus of an automatic bobbin changing type is provided with two bobbin holders projecting from a turret table formed in a circular disc and spaced a predetermined distance from each other. When a package wound on one of the bobbin holders reaches a predetermined amount, the turret table is turned around a central axis upon changing of winding of the yarn.
According to another apparatus, disclosed in Japanese Patent Application Laid-open No. Sho 63-57477, two bobbin holders are independently and pivotably supported between a winding position and a stand-by position, and a friction roller is selectively in contact with one of the two bobbin holders.
According to the apparatus disclosed in the Japanese Patent Publication No. Sho 57-25466, two bobbin holders project from the circular turret table at predetermined spaced positions, and when a package wound on one of the bobbin holders reaches a predetermined amount, the turret table is turned with the two bobbin holders.
Accordingly, a large space is required for installing such a winding apparatus, and thus the distance between adjacent winding apparatus must also be large, and consequently, a large amount of space required for installing a large number of winding apparatus.
The apparatus disclosed in Japanese Patent Application Laid-open No. Sho 63-57477 requires a large space which is twice that required for an apparatus of a manual changing type since two bobbin holders are independently and pivotably supported between a winding position and a stand-by position.
The present inventor previously proposed in U.S. patent application Ser. No. 975,965, now U.S. Pat. No. 5,246,177, a yarn winding apparatus of an automatic bobbin changing type, by which the above-described problems can be obviated and the space required for installation can be minimized. The proposed apparatus is provided with a plurality of bobbin holders, and when a package wound on one of the bobbin holders reaches a predetermined amount, winding of the yarn is changed to another bobbin holder. The apparatus comprises:
a path formed along a closed loop for guiding the plurality of bobbin holders along a winding position, a doffing position, an empty bobbin donning position, a stand-by position, a changing position and the winding position; and PA1 a means for independently moving the plurality of bobbin holders along the bobbin holders guiding path. PA1 a first slider guide means for guiding the bobbin holders; PA1 a second slider guide means for guiding the bobbin holders; PA1 sliders disposed so as to be movable along the first and second slider guide means; and PA1 carriers mounting the bobbin holders thereon which are capable of being transferred between the sliders on the first and second slider guide means.
The proposed automatic bobbin changing apparatus can achieve the intended objects of minimization of the space required for installation. However, the apparatus uses an endless gear means for independently moving the plurality of bobbin holders along the bobbin holders guiding path and chains for moving the bobbin holders along the endless gear means. Further, since the endless gear means have to be disposed for the two bobbin holders, respectively, they have to be stacked in parallel on the winding apparatus. Thus, there is a problem in that the construction of the proposed apparatus is very complicated. In addition, when the bobbin holders are moved, they are moved along the endless gear means at all positions on the bobbin holder guiding path formed in a closed loop, and thus, the precision of the movement is substantially the same regardless of the positions on the guiding path. In other words, the highly precise control of bobbin holder movement which is required around the winding position is also achieved for the rest of the guiding path, and accordingly, the control means is very expensive.